Cold rads

[stratplus]

Hall rad and kitchen rad back to back stone cold. Upstairs all hot, another 3 downstairs ok. Turned all upstairs rads off still the same two cold. Turned off the good 3 downstairs then boiler goes off.
Turned off cold rad at lockshields x2 and crack the nut, full bowl under and vaguely luke warm. Re-open rads and still sone cold.
Any ideas?

 

[kay-jay]

Yep you have a blockage on that leg that feeds the back to back rads which is why the boilet knocks off ss it overjeats cos theres no circulation. If it was air it would have cleared.

Microbore by amy chance? Manifold blocked port?

 

[stratplus]

15mm plastic to copper tails.
Brand new system, new build. Water pressure to the rad is fine.
Possibility of piping wrong? Last rads on the run, pipe two flows/ two returns into the same rad?

 

[kay-jay]

Prolly both piped to either the flo or return then

 

[stratplus]

Two houses like this, exactly the same problems.

 

[kay-jay]

Same guy do the plumbing in both houses?

 

[stratplus]

Dont know but probably

 

[stratplus]

Another one, an air source heat pump not working. Flow outside on heat pump gets hot on the flexi connection but the copper pipe atrached to it is cold ie no circulation. I reckon primary flow and return are crossed in a/c. Same site.

 

[kay-jay]

Sounds like it.
Do you have yo put these right then mate?

 

[stratplus]

Unfortunately yeah. Got sent to commission them

 

[kay-jay]

Good luck pal.

 

[stratplus]

The two rads were piped right under the floor but wrong where they joined the rads. One rad had two flows the other two returns.
The heat pump issue was a stuck flow setter.

 

[AWheating]

simular probs on the job ive been on paul. xcrossed pipes etc...... nice to have a warm toilet tho

 

[stratplus]

Pmsl, loving the warm toilet.